|San Diego Freeway|
|Auxiliary route of I-5|
|Defined by Streets and Highways Code § 615|
|Maintained by Caltrans|
|Length||72.415 mi (116.541 km)|
|South end||I-5 in Irvine|
|North end||I-5 near San Fernando|
|Counties||Orange, Los Angeles|
Interstate 405 (I-405) is a major north-south auxiliary Interstate Highway in Southern California. The entire route is known as the northern segment of the San Diego Freeway. I-405 is a bypass auxiliary route of I-5, running along the southern and western parts of the Greater Los Angeles urban area from Irvine in the south to near San Fernando in the north.
I-405 is a heavily traveled thoroughfare by both commuters and freight haulers along its entire length and is the busiest and most congested freeway in the United States. The freeway's annual average daily traffic between exits 21 and 22 in Seal Beach reached 374,000 in 2008, making it the highest count in the nation. It has played a crucial role in the development of dozens of cities and suburbs along its route through Los Angeles and Orange counties. It also serves Los Angeles International Airport (LAX), Long Beach Airport (LGB) and Orange County's John Wayne Airport (SNA).
I-405 begins at the El Toro Y interchange in southeastern Irvine in Orange County, splitting from its parent I-5 and inheriting that route's San Diego Freeway title; I-5 continues north as the Santa Ana Freeway. The freeway passes immediately south of the Irvine Spectrum Center mall before intersecting with State Route 133 (SR 133). It then continues through Irvine, passing north of UC Irvine and then along the northern boundary of John Wayne International Airport. After passing the airport, the freeway enters Costa Mesa and has an interchange with SR 55. It passes South Coast Plaza before a partial interchange with SR 73, which serves as a partially-tolled bypass of I-405 between Costa Mesa and Laguna Niguel.
The freeway then travels through Fountain Valley and along the edges of Westminster and Huntington Beach before entering Seal Beach, where it begins to run concurrently with SR 22. It continues along the northern edge of Seal Beach, passing between Naval Weapons Station Seal Beach and Joint Forces Training Base Los Alamitos, before SR 22 splits from I-405 and continues west while the freeway turns north. I-405 then intersects the southern end of I-605 before crossing the San Gabriel River and entering Los Angeles County.
I-405 enters Los Angeles County in the city of Long Beach. It passes to the north of California State University, Long Beach and then along the south of Long Beach Airport. The freeway then intersects with I-710 before entering Carson twice (to be more detailed here: once passing South McHelen Avenue right before the Alameda Street/CA-47 exit -The east side of Alameda and 223rd Street that connect the NB/SB ramps is in the tail end of Wilmington for a brief second / first time in Los Angeles- and the second time entering Carson happens past Alameda Street). It passes near California State University, Dominguez Hills and Dignity Health Sports Park, home of Major League Soccer club LA Galaxy as well meets I-110.
After leaving Carson, I-405 briefly enters the city of Los Angeles for a second time by passing through the Harbor Gateway, a strip of land connecting San Pedro to the rest of the city. The freeway then continues to roughly parallel the contour of the coastline as it passes through the South Bay communities of Torrance, Lawndale, Redondo Beach, Hawthorne, and El Segundo. The freeway then encounters I-105 on the southeastern corner of LAX. It passes to the east of the airport, serving it with exits at Imperial Highway and Century Boulevard.
I-405 next passes through Inglewood, coming near the site of SoFi Stadium, home to the Los Angeles Rams and Los Angeles Chargers of the National Football League. It then passes through Westchester and Culver City where it meets SR 90, the Marina Freeway. It serves the Los Angeles neighborhoods of Mar Vista and West Los Angeles while passing a few miles east of Santa Monica, intersecting with I-10 in the process. The freeway continues into Westwood, passing just to the west of UCLA. It then passes the Getty Center as it ascends the Sepulveda Pass through the Santa Monica Mountains.
After cresting the mountains, I-405 descends into the San Fernando Valley, intersecting U.S. Route 101 (US 101) in the Sherman Oaks neighborhood of Los Angeles. The freeway then continues due north through the western part of the valley, passing east of Van Nuys Airport and California State University, Northridge. It intersects SR 118 in the Mission Hills area before ending in a merge with I-5 near San Fernando.
I-405 is part of the California Freeway and Expressway System, and is part of the National Highway System, a network of highways that are considered essential to the country's economy, defense, and mobility by the Federal Highway Administration. The freeway is known as the San Diego Freeway, and parts of it are less commonly known as the Sepulveda Freeway (after Sepulveda Boulevard).
The freeway's congestion problems are legendary, leading to jokes that the road was numbered 405 because traffic moves at "four or five" miles per hour, or because drivers had spent "four or five" hours to travel anywhere. Indeed, average speeds as low as 5 miles per hour (8.0 km/h) are routinely recorded during morning and afternoon commutes, and its interchanges with the Ventura Freeway (US 101) and with the Santa Monica Freeway (I-10) each consistently rank among the five most congested freeway interchanges in the United States. As a result of these congestion problems, delays passing through the entire Los Angeles metropolitan area using this bypass route instead of merely using the primary route I-5 through Downtown may be present.
I-405 is the only major north-south freeway in the densely populated areas between West Los Angeles and Downtown, crossing the Santa Monica Mountains and connecting San Fernando Valley and the Los Angeles basin. Another parallel freeway is proposed to connect the Valley and the LA basin (the Laurel Canyon Freeway or La Cienega Freeway), but has faced upper class home-owner opposition. Despite four years of construction disruptions, billions of dollars of public money, LA Times commentary claims traffic with the lane expansions is actually just as bad or worse.
Unlike some of the other major travel corridors in the region (such as Interstate 5 which parallels the LOSSAN Corridor), I-405 has no rail-based public transit which parallels it along the west side of Orange and Los Angeles counties. There is a proposal for a Sepulveda Pass Transit Corridor which would parallel the 405 through Sepulveda Pass, one of the major bottlenecks on the route, which would ease congestion by providing an alternative to driving.
I-405 was approved as a chargeable Interstate (in other words, an Interstate financed with federal funds) in 1955. Construction began in 1957 with the first section, mostly north of LAX Airport, completed in 1961 (signed as SR 7) followed by sections west of I-605 within the following few years. The highway was renumbered to I-405 during the 1964 renumbering. The final section covering most of Orange County opened in 1969. Construction required the already existing Mulholland Highway to be re-routed 1.1 miles (1.8 km) to the south along a new 579-foot-long (176 m) bridge, the Mulholland Drive Bridge, to span I-405.
A section of I-405 was closed over the weekend of Friday, July 15, 2011 as part of the Sepulveda Pass Improvements Project. Before the closing, local radio DJs and television newscasts referred to it as "Carmageddon" and "Carpocalypse", parodying the notion of Armageddon and the Apocalypse, since it was anticipated that the closure would severely impact traffic.
In reality, traffic was lighter than normal across a wide area. The California Department of Transportation (Caltrans) reported that fewer vehicles used the roads than usual, and those who did travel by road arrived more quickly than on a normal weekend. The Metrolink commuter train system recorded its highest-ever weekend ridership since it began operating in 1991. Ridership was 50% higher than the same weekend in 2010, and 10% higher than the previous weekend ridership record, which occurred during the U2 360° Tour in June 2011.
In response to jetBlue Airlines' offer of special flights between Bob Hope Airport in Burbank and Long Beach Airport, a distance of only 29 miles (47 km), for $4, a group of cyclists did the same journey in one and a half hours, compared to two and a half hours by plane (including a drive to the airport from West Hollywood 90 minutes in advance of the flight and travel time to the end destination). There was also some debate about whether the Los Angeles area could benefit from car-free weekends regularly.
The Los Angeles County Metropolitan Transportation Authority had full closure of a 10-mile (16 km) stretch of I-405 on the weekend of September 29-30, 2012, while construction crews worked to demolish a portion of the Mulholland Bridge.
Researchers at the University of California, Los Angeles used the closure of I-405 to study particulate matter air pollution. The researchers took air samples before, during, and after the closure. The researchers found an 83% reduction in ultrafine particles, 55% reduction in fine particle matter, and 62% less black carbon.
The $1 billion Sepulveda Pass Improvements Project added a high-occupancy vehicle lane and associated changes to freeway entrances, exits, and underpasses along a 10-mile stretch through the Sepulveda Pass between I-10 and U.S. 101/Ventura Boulevard. The project was completed as a design-build in contrast to the traditional design-bid-build used typically in infrastructure improvement. This section of I-405 was closed for a weekend in mid-July 2011 to demolish the Mulholland Drive Bridge, and a 10-mile (16 km) section was closed for the last weekend of September 2012.
Jamzilla was the name for the I-405 closure on President's Day Weekend 2014. There were lane closures and complete closures on I-405 starting February 14 at 10 p.m. until February 18 at 6 a.m. to pave and re-stripe the northbound lanes.
On May 23, 2014, the 10-mile (16 km) high-occupancy vehicle lane was opened to traffic.
Proposed changes between the Manchester and Century Boulevard interchanges in the City of Inglewood are to provide a new southbound on-ramp and a new northbound off-ramp for Arbor Vitae Street, to reconstruct and widened the Arbor Vitae Street over-bridge and replace the Century Boulevard overcrossing structure. This work would reduce congestion on the approach to LAX. The California Department of Transportation has not yet issued a start date for this work.
The Orange County Transportation Authority is currently adding a high-occupancy toll (HOT) express lane and one mixed flow lane in each direction between SR 73 in Costa Mesa and I-605 in Seal Beach. The I-405 Improvement Project started construction in 2018 and is scheduled to be expected by completed in 2023.
Following the 1966 UCLA-USC rivalry football game, USC was voted into the Rose Bowl despite the UCLA team's having defeated the Trojans--with both teams having only one loss during the season. UCLA students protested by blocking the freeway's northbound lanes at Wilshire Boulevard.
While dangerous high-speed chases along the San Diego Freeway are not uncommon, perhaps the most famous chase in its history was also one of the slowest. On the afternoon of June 17, 1994, former athlete and actor O. J. Simpson, who was accused of murdering his ex-wife Nicole Brown Simpson and waiter Ron Goldman, took to the freeway in a white Ford Bronco (driven by former teammate Al Cowlings) with police in pursuit. A widely televised low-speed chase ensued and ended hours later when Simpson returned to his Brentwood, Los Angeles, home and surrendered to law enforcement.
On March 10, 2019, the portion of I-405 between the Ventura Freeway (US 101) and Burbank Boulevard in the Sherman Oaks area was closed in both directions as a propane tanker truck carrying more than 9,000 US gallons (34,000 l) of flammable gas overturned along the southbound lanes of I-405. No explosion resulted from the incident.
I-405 was the location for the short film 405.
The Jimmy Eat World song "If You Don't, Don't", from the album Bleed America includes the line "Don't you know I'm thinking (know I'm thinking), driving 405 past midnight".
The Death Cab for Cutie song "405" on their second studio album, We Have the Facts and We're Voting Yes, may be incorrectly associated with California's I-405. The song is actually referring to I-405 in Seattle, as the band is from Bellingham.
In his 2016 song "No More Parties in L.A." Kanye West raps the following line: "Textin' and drivin' down Mulholland Drive/That's why I'd rather take the 405."
Maggie Lindemann's 2021 song Different contains the line "2 a.m., windows down, drivin' on the 405"
|Orange||Irvine||0.00||0.00||I-5 south (San Diego Freeway south) - San Diego||Southern terminus; former US 101 south; no access to I-5 north; I-5 exit 94A; San Diego Freeway continues as I-5 south|
|0.72||1.16||1A||Lake Forest Drive||No northbound exit|
|1B||Bake Parkway||No northbound exit|
|1C||Irvine Center Drive||Signed as exit 1 northbound|
|?||I-5 south||HOV access only; southbound exit and northbound entrance|
|1.57||2.53||2||SR 133 (Laguna Freeway) to toll road - Laguna Beach||No northbound exit to SR 133 north; SR 133 exit 8|
|2.65||4.26||3||Shady Canyon Drive / Sand Canyon Avenue|
|3.72||5.99||4||Jeffrey Road / University Drive|
|7.57||12.18||8||MacArthur Boulevard - John Wayne Airport|
|Costa Mesa||8.51||13.70||9A||SR 55 (Costa Mesa Freeway)||SR 55 north exit 6, south exits 6A-B|
|?||SR 55 north||HOV access only|
|9.28||14.93||9B||Anton Boulevard / Avenue of the Arts / Bristol Street||Northbound signage|
|Bristol Street||Southbound signage|
SR 73 south (Corona del Mar Freeway) to SR 55 south (Costa Mesa Freeway) - San Diego via toll road
|Southbound exit and northbound entrance|
|11||South Coast Drive||Northbound exit only|
|10.59||17.04||11A||Fairview Road||Signed as part of exit 11 northbound|
|11B||Harbor Boulevard / Susan Street - Costa Mesa|
|Fountain Valley||12.24||19.70||12||Euclid Street / Newhope Street / Ellis Avenue|
|13.55||21.81||14||Brookhurst Street - Fountain Valley|
|14.59||23.48||15A||Warner Avenue west||Northbound signage|
|Warner Avenue east||Southbound signage|
|Fountain Valley-Huntington Beach-|
|14.98||24.11||15B||Magnolia Street||Northbound signage|
|Magnolia Street / Warner Avenue west||Southbound signage|
|Huntington Beach-Westminster line||16.31||26.25||16||SR 39 (Beach Boulevard) - Westminster, Huntington Beach|
|Westminster||17.52||28.20||18||Bolsa Avenue / Goldenwest Street||Goldenwest Street is signed as Golden West St.|
|18.93||30.46||19||Westminster Boulevard / Springdale Street||Springdale Street not signed northbound; signed as exits 19A (Springdale Street/Westminster Boulevard east) and 19B (Westminster Boulevard west) southbound|
|20.33||32.72||20||Bolsa Chica Road||Southbound exit and entrance only|
|Westminster-Garden Grove line||20.52||33.02||21||SR 22 east (Garden Grove Freeway) / Valley View Street - Garden Grove||Southern end of SR 22 concurrency; southbound exit includes Garden Grove Boulevard and Valley View Street|
|?||SR 22 east||HOV access only; southbound exit and northbound entrance|
|Seal Beach||22.41||36.07||22||Seal Beach Boulevard / Los Alamitos Boulevard||Former SR 35|
|23.05||37.10||23||SR 22 west - Long Beach||Northern end of SR 22 concurrency; northbound exit and southbound entrance; I-605 exit 1A|
|?||I-605 north||HOV access only; northbound exit and southbound entrance|
|Seal Beach-Long Beach line||23||SR 22 west (7th Street) - Long Beach||Southbound exit and northbound entrance; SR 22 exit 2, I-605 south exit 1A|
|23.81||38.32||24A||I-605 north (San Gabriel River Freeway)||Signed as exit 24 northbound; I-605 north exit 1A, south exits 1B-C; SR 22 exit 2|
|23.95||38.54||San Gabriel River|
|Los Angeles||Long Beach||24.40||39.27||24B||Studebaker Road||Southbound exit and northbound entrance|
|25.06||40.33||25||Palo Verde Avenue|
|25.59||41.18||26A||Woodruff Avenue||No southbound exit|
|26.13||42.05||26B||Bellflower Boulevard||Signed as exit 26 southbound|
|27.27||43.89||27||SR 19 (Lakewood Boulevard) - Long Beach Airport|
|28.83||46.40||29||Spring Street / Cherry Avenue - Signal Hill||Signed as exits 29A (south) and 29B (north)|
|Signal Hill||29.37||47.27||29C||Orange Avenue|
|Signal Hill-Long Beach line||29.85||48.04||30A||Atlantic Avenue|
|Long Beach||30.11||48.46||30B||Long Beach Boulevard||Former SR 15|
|31.37||50.49||32A||Pacific Avenue||Southbound exit and northbound entrance|
|31.83||51.23||32||I-710 (Long Beach Freeway) - Long Beach, Pasadena||Signed as exits 32A (north) and 32B (south) northbound, and 32B (south) and 32C (north) southbound; I-710 exit 4|
|31.87||51.29||32C||Hughes Way / Santa Fe Avenue||Signed as exit 32D southbound; Hughes Way not signed southbound|
|Carson||32.55||52.38||33A||Alameda Street (SR 47 south)|
|35.00||56.33||35||Avalon Boulevard - Carson||Northbound exit to Avalon Boulevard south is via exit 34.|
|36.37||58.53||36||Main Street||Northbound exit and southbound entrance|
|36.74||59.13||37A||I-110 (Harbor Freeway) - San Pedro, Los Angeles||Signed as exit 37 northbound; former US 6; I-110 exit 9|
|Los Angeles||37.01||59.56||37B||Vermont Avenue||Southbound exit and northbound entrance|
|37.60||60.51||38A||Normandie Avenue - Gardena|
|Los Angeles-Torrance line||38.19||61.46||38B||Western Avenue|
|Torrance||39.22||63.12||39||Crenshaw Boulevard - Torrance|
Artesia Boulevard to SR 91
|Signed as exit 40A southbound; former SR 91|
|Lawndale||40.65||65.42||40B||Redondo Beach Boulevard - Redondo Beach||Southbound exit and northbound entrance|
|41.36||66.56||42A||SR 107 (Hawthorne Boulevard) - Lawndale|
|Lawndale-Redondo Beach line||42.01||67.61||42B||Inglewood Avenue|
|Hawthorne||42.98||69.17||43||Rosecrans Avenue - Manhattan Beach||Signed as exits 43A (east) and 43B (west) southbound|
|43.99||70.80||44||El Segundo Boulevard - El Segundo|
|Lennox||44.95||72.34||45A||I-105 (Century Freeway) - El Segundo, Norwalk||Signed as exit 45 southbound; serves Los Angeles International Airport; I-105 east exit 2, west exit 2B|
|44.95||72.34||45B||Imperial Highway||Southbound exit is part of exit 46.|
|Inglewood||46.00||74.03||46||Century Boulevard - LAX Airport|
|47.13||75.85||47||Manchester Boulevard / La Cienega Boulevard / Florence Avenue||Manchester Boulevard was former SR 42.|
|Westchester||48.05||77.33||48||La Tijera Boulevard|
|48.33||77.78||49A||Howard Hughes Parkway / Sepulveda Boulevard||Signed as exit 49 southbound|
|Culver City||49.23||79.23||49B||Sepulveda Boulevard / Slauson Avenue (SR 90 east)||Northbound exit only; SR 90 exit 2|
|49.70||79.98||50A||Jefferson Boulevard||Signed as exit 50B northbound|
|50B||SR 90 (Marina Freeway) / Slauson Avenue - Marina del Rey||Signed as exit 50A northbound; no access from I-405 north to SR 90 east; SR 90 exit 2|
|50.97||82.03||51||Culver Boulevard / Washington Boulevard - Culver City|
|51.22||82.43||52||Venice Boulevard (SR 187) / Washington Boulevard|
|Los Angeles||52.94||85.20||53A||National Boulevard||Northbound exit and southbound entrance|
|53.31||85.79||53B||I-10 (Santa Monica Freeway) - Santa Monica, Los Angeles||Signed as exit 53 southbound; I-10 exits 3A-B|
|53.96||86.84||54||Olympic Boulevard / Pico Boulevard||Southbound exit and northbound entrance; former SR 26|
|54.63||87.92||55A||SR 2 (Santa Monica Boulevard)||Former US 66|
|55B||Wilshire Boulevard||Signed as exits 55B (east) and 55C (west) southbound|
|56.27||90.56||56||Montana Avenue||Northbound exit only; demolished|
|56.77||91.36||57A||Sunset Boulevard||Signed as exit 57 southbound|
|57.06||91.83||57B||Moraga Drive||Northbound exit and entrance|
|58.54||94.21||59||Getty Center Drive|
|60.80||97.85||61||Mulholland Drive / Skirball Center Drive|
|Sherman Oaks||62.78||101.03||63A||Ventura Boulevard / Sepulveda Boulevard / Valley Vista Boulevard|
|63.20||101.71||63B||US 101 (Ventura Freeway) - Ventura, Los Angeles||US 101 exit 19A|
|Van Nuys||65.13||104.82||65||Victory Boulevard - Van Nuys|
|66||Sherman Way - Van Nuys Airport||Signed as exits 66A (east) and 66B (west) northbound|
|North Hills||67.53||108.68||68||Roscoe Boulevard - Panorama City|
|Mission Hills||70.03||112.70||70||Devonshire Street - Granada Hills|
|70.62||113.65||71A||SR 118 (Ronald Reagan Freeway) - Simi Valley||Signed as exit 71 southbound; no southbound exit to SR 118 east or northbound entrance from SR 118 west; SR 118 east exit 42A, west exit 42B|
|71.01||114.28||71B||San Fernando Mission Boulevard||Northbound exit and southbound entrance|
|71.53||115.12||72||Rinaldi Street - Mission Hills|
|72.42||116.55||I-5 north (Golden State Freeway) - Sacramento||Northern terminus; no access to I-5 south; I-5 exit 158|
|1.000 mi = 1.609 km; 1.000 km = 0.621 mi|
During 53 hours of closure, the north side of the Mulholland Bridge will be demolished as part of the $1 billion Sepulveda Pass Improvements Project.